Which material earned Alan Heeger, Alan MacDiarmid and Hideki Shirakawa the 2000 Nobel Prize in Chemistry?

Conducting polymers earned Alan Heeger, Alan MacDiarmid and Hideki Shirakawa the 2000 Nobel Prize in Chemistry. These carbon-based polymers can conduct electricity when their electronic structures are modified, or doped.

Ordinary polymers are commonly associated with electrical insulation, but certain polymers contain conjugated backbones with alternating single and double bonds. Removing or adding electrons creates mobile charge carriers along the chain, allowing electrical conductivity.

The laureates’ work focused especially on polyacetylene. Shirakawa produced polyacetylene films, while Heeger and MacDiarmid showed that doping could increase their conductivity dramatically. Their research helped establish plastics as materials with useful electronic properties.

Conducting polymers are not the same as metals: their conductivity, flexibility, weight and processing characteristics differ. Later applications and research have included organic electronics, light-emitting devices, sensors and electrochemical systems.